Mobile or portable computers, such as laptops or palmtops, are becoming increasingly popular in that they provide users with the capability to work or operate away from an office or other fixed location. The design of such mobile computers is of necessity a trade off between on the one hand the computing power, memory size and data storage capacity of the computer, and on the other hand weight and power consumption, to provide a computer which has sufficiently useful operating capacities but which may still be easily carried by a user and have a sufficient long battery life to be able to operate for a useful period away from a power source.
Conventionally, it is known to complement such mobile computers with a base station. The base station receives or otherwise functionally interacts with the mobile computer, and provides additional capabilities such as a power supply, a network connection, connection to a better display, access to a more powerful processor and so on.
This solution has however a number of disadvantages. When the user has a mobile computer for travelling and a conventional desktop for office use, the information held by the mobile computer and the desk top computer need to be synchronized. This requires installed software on each computer to be exactly the same and requires a careful synchronization mechanism such that appropriate data is stored on both computers when possible and is transferred from one computer to another when required. Conventionally, when the user docks the mobile computer and the base station, the user will have to close open applications on the mobile computer before operating desktop programs.
It is also known to provide a mobile computer which is responsive to its operating environment. For example, it is known to provide a mobile computer which increases its operating frequency when connected to a mains power supply, and when running on battery, reduces its operating frequency to extend the battery life. However, this technique has certain limitations. The range of frequencies is generally not very large so the mobile computer will not operate optimally in either state and is in any case dependent on other parameters such as the memory type, cache size and so on. The performance limitations on a computer also depend in part on the cooling capability of the computer, that is the possibility to cool the CPU. In a mobile computer, the room for providing cooling apparatus such as fans and heatsinks is relatively limited.
A third solution would be to purpose-build a very high power but light weight mobile computer, but such a solution would be particularly expensive.
An aim of the present invention is to provide a mobile computer and a base station where the mobile computer has maximum autonomy including relatively low power consumption and weight but correspondingly relatively low performance, and a base station which has a relatively high performance processor, with a simplified transition from the mobile computer to the base station.